Ke'erqin Deserts, in eastern Inner Mongolia, has relatively favorite water and heat conditions for agriculture. Based on analyses of human reclamation activities, area of cultivated land in one typical region, and spatial structures and inner differences in/among major counties, land use pattern changes during last 50 years in Ke`erqin Deserts is discussed. The result shows that, after four times large scale reclamation since the foundation of P. R. China, Land use pattern Changed vastly in Ke`erqin Deserts. The major feature of that change is northern ward movement of both northern agriculture cultivation frontier and farmland gravity in Ke`erqin Deserts. And the major driving force of that change is increases in population and direction of national development polices, rather than natural conditions of rainfall and temperature, which have little change compared with 50 years ago. Over reclamation without proper protecting measures has caused environmental worsening and soil desertification in Ke'erqin Deserts.